Colt M.A.R.C.901

Colt M.A.R.C.901 LE901-16SE www.combatrifle.com

Colt M.A.R.C.901 LE901-16SE

Introducing the Colt M.A.R.C.901™ family of rifles. Each new rifle in the M.A.R.C.901 family is an evolution of the LE901-16S, which means the upper receiver group can be easily swapped out for any Colt upper receiver chambered in .223 Rem (5.56 x45 NATO) with the conversion kit (sold separately). Bolt and magazine controls are ambidextrous for flexibility and ease of use.

Be it for whitetail hunting in Maine, target practice at the range or law-enforcement use, the Colt M.A.R.C.901 family of rifles have the power and versatility you need. Exceptional accuracy is assured by its full floated, 16.1” chrome lined barrel, and users can now find their perfect balance with customized mounting of accessories such as optics, bipods, lasers and more.

Colt LE901-16SE Special Features

 

  • User Configurable 1-Piece Upper Receiver with Back Up Iron Sights (BUIS)
  • Full Floated Barrel
  • Bayonet Lug and Flash Hider
  • Ambidextrous Controls
  • Accepts Mil-Spec 5.56 Colt Uppers

Colt LE901-16SE Specifications

  • MSRP – $1,399
  • Caliber -.308 Win
  • Barrel 0Length (in.) 16.1″ Heavy
  • Bore – Chromed, 4 Grooves, 1-12″ RH Twist
  • Collapsed Length – 34.24″
  • Weight – 8.4 LBS
  • Action – Direct Gas System, Locking Bolt
  • Finish – Matte Black
  • Front Sight – Flip-Up, Adjustable Post for Elevation
  • Rear Sight – Flip-Up, Adjustable for Windage
Colt M.A.R.C.901 AR901-16S www.combatrifle.com

Colt M.A.R.C.901 AR901-16S

Colt AR901-16S Special Features

  • User Configurable Tubular Handguard
  • Full Floated Barrel
  • Accepts Mil-Spec 5.56 Colt Uppers

Colt AR901-16S Specifications

  • MSRP – $1,399
  • Caliber -.308 Win
  • Barrel 0Length (in.) 16.1″ Heavy
  • Bore – Chromed, 4 Grooves, 1-12″ RH Twist
  • Collapsed Length – 34.24″
  • Weight – 8.4 LBS
  • Action – Direct Gas System, Locking Bolt
  • Finish – Matte Black
  • Front Sight – None
  • Rear Sight – None

Colt M.A.R.C.901


Colt Sporter | AR15 Upgrade | AR 15 Rifle | HBAR

Colt Sporter AR15 Upgrade

Colt Match HBAR Sporter

Colt Match HBAR Sporter Before the Colt Sporter AR15 Upgrade

Colt Sporter AR15 Upgrade

Colt Sporter AR15 Upgrade

 

Update: August 10, 2015 – Interesting to look back at this project that was completed June 26, 2010. It’s nice to see that in 2015 this build is still a very relevant and well though out project. Not to say there have not been changes. My eyesight has gone downhill and I can no longer use the EOTech. It has been replaced with a Browe Sport Optic. The Taclight has been replaced with a Surefire. The change was not for anyreason other than internet friend Ernie aka Microgunner (RIP) got a few NIB units at his pawn shop. It’s also important to note at the time this project was started it was very difficult to obtain AR-15 hardware.

Colt Sporter AR15 Upgrade

I have the unfortunate pleasure of living in a state that implemented its own version of an Assault Weapon Ban. Because this law was in place before the now sunset Federal Assault Weapon ban this ban will most likely remain in place forever. I was however, lucky enough to buy a Colt Match HBAR before the ban. This weapon is a “registered assault rifle” in the eyes of the state. Because of this “Pre ban” status of this weapon I am able to customize this rifle with all the best upgrades that folks in other states take for granted. Below is a list of the A-15 parts used in this project along with the rationale for their selection.


Colt Sporter Tactical AR-15 – Upper Receiver

White Oak Armament 16 Stainless Steel Match Grade Barrel

White Oak Armament makes some of the finest AR-15 barrels in the business. I was quite surprised to find Brownells had the White Oak Armament 16 Stainless Steel Match Grade Barrel in stock. The White Oak Armament barrel has the Wylde Chamber. This makes it suitable for .223 and 5.56 ammo. The barrel is bead blasted stainless steel.

Precision-machined stainless steel barrels feature a .223 Wylde chamber that helps maximize the long-range performance of your AR-15 with both .223 Remington and 5.56x45mm NATO ammunition. With 6-groove, 1-7″ button rifling for accuracy and M4-type feed ramps for reliable feeding, these barrels help you reach out to distant targets with issued or magazine-length ammunition.

M4 AR 15 Stripped Upper Receiver

I ended up purchasing two stripped upper receivers. One matte black and the other black teflon. It was my hope that the color of one of the receivers would reasonably match the color of my Colt Sporter lower. Neither did and the matte unit has been sent out for anodizing of the correct color Colt Gray. More info below. Note: The color issue is a colt specific issue from the early 1990’s

LaRue Tactical AR 15 13.2 Handguard LT15-13.2

This choice took me quite a while to decide upon. I finally narrowed it down to a Daniel Defense M4 12.0 Rail and LaRue Tactical AR 15 13.2 Handguard LT15-13.2 finally deciding to run with the Larue. There were a few reasons I settled on the Larue unit. The main reason I believe was my good friend Rob at Ranier Arms planted a subliminal message that covering up as much barrel as possible would be most appealing to the eye. Naturally Rob was correct. I had no intent on utilizing a front sight gas block so the 13.2″ length covers the Daniel Defense Low Profile Gas Block nicely. The LT15-13.2 also has a very comfortable profile. The LT15-13.2 is taller than it is wide.

LARUE TACTICAL LT15-13.2 AR 15 Handguard

LARUE TACTICAL LT15-13.2 AR 15 Handguard

Here is the description straight from Larue Tactical:

Ideal for 16″-20″ barreled uppers that need maximum rail space. The 13.2’s length covers all gas blocks, including full-lengths, providing true free-float. Our two-pin proprietary barrel nut system with its locking anti-slip plate, sets LaRue handguard’s apart from the competition. Once properly installed, there is no chance of movement whatsoever. The side and bottom rails are tucked closer to the barrel, keeping the profile narrower and more streamlined. LaRue handguard’s also include integral QD sling-swivel sockets at the base of each side for convenient mounting 2-point slings. Additionally, our Free-float Rail system provides an excellent heat-sinking feature that pulls throat-damaging heat away from the chamber area. Another heat-sinking benefit is the elimination of pressure-spikes, which some feel is the cause of a large part of pre-mature bolt failures.

Gas Block

Yankee Hill Machine Low Profile Gas Block YHM-9383

Picture of YHM 9383 Gas Block AR 15

YHM 9383 Gas Block AR 15

If you have been following this project you might recall I had originally specified the Daniel Defense Low Profile Clamp On Gas Block (now discontinued). Unfortunately the Daniel Defense would not work with the Larue Handguard. Not wanting to buy another wrong part I ended up with two possible options. option one was to get a Larue Gas Block which would surely fit or Option two buy the smallest gas block I could find. I chose the latter for two reasons, cost and availability. I the ordered the Yankee Hill Machine Low Profile Gas Block YHM-9383.

 

Bravo Company BCM Gunfighter Charging Handle GFH MOD 3

BCM Gunfighter Charging Handle GFH MOD 3 AR 15 Charging Handle

BCM Gunfighter Charging Handle GFH MOD 3 AR 15 Charging Handle

Bravo Company does a great job of explaining why an AR-15 should include a BCM Gunfighter Charging Handle. Here’s what they say:

When the AR15 system was first introduced to and fielded by the US Military in the 1960s, the manual of arms for an infantryman was significantly different than what currently exists today. To charge the rifle the shooter released their hand from a firing grip, grabbed each side of the charging handle with the thumb and forefinger or the first two fingers , (while applying pressure to the latch) pulled the charging handle all the way to the rear, and then released it to charge the weapon.

Like everything else in the last 45 years, tactics and weaponry have undergone a continuous evolution. Red dot optics get the shooter on target quicker, shorter barrels allow the operator to more quickly negotiate tighter urban areas, and operator’s manipulations of the weapon system have become much more efficient and faster. The current manual of arms has the operator maintaining a firing grip almost continuously while manipulating the weapon with the non-dominant hand in an effort to more quickly get the weapon ready to fire. With that premise, most weapon manipulations are done only with the shooter’s support hand; to include operating the charging handle.

In order to perform an immediate action or charge the carbine, current CQB techniques have the operator racking the charging handle to the rear using their support side hand only. This is done in one swift and strong movement. With the operator’s firing grip maintained, the weapon again has a loaded chamber, and the shooter can immediately bring a hot weapon back into the fight.

The current use of extended tactical latches has made this movement much more efficient. The only drawback to this type of manipulation is all the force used to rack the charging handle rearward goes into the extended tactical latch and is then transferred into the roll pin. With this scenario, the entire operation becomes contingent on the sheer strength of this tiny 1/16” roll pin, and its’ ability to take continuing blows. Repeated and forceful support hand only racking of the charging handle eventually can lead to breaking the roll pin and loosing the latch completely. With the latch blown out, the charging handle will not stay secured to the receiver as the bolt is moving back and forth during each cycle of the weapon’s action. Not a good situation on a two way range.

We have been very fortunate to receive continuing feedback from trainers and operators alike for several years now regarding these issues. Internally we have seen this many times while in the course of continually test firing weapons before sale. Initially we matched up a couple prototype solutions, but in conversations with Eric at VLTOR, he was able to develop a better design at a better price for the consumer. (VLTOR patent pending)

he BCMGUNFIGHTER™ Charging Handle and extended latches feature internal redesigns to direct the force off of the roll pin and into the body of the charging handle during support hand only manipulations. This new design has a built in backstop engineered into the extended latch and into the charging handle. As the latch is opened up, its’ travel is limited by these flat surface backstops. With this travel limiting feature, the stress is taken off the roll pin, and is now redirected into the entire body of the charging handle.

The BCMGUNFIGHTER™ Charging Handle offers two significant advantages.

  • Since the tiny roll pin is no longer the weak point – it is a much stronger system and tactical latch will stay intact even under repeated support side only manipulation.
  • With the force kept inside the body of the handle, when the handle is pulled directly to the rear, it moves directly to the rear and does not angle off to the outboard side. A much smoother operation.

Visit Bravo Company for images illustrating the differences in design.

 

VLTOR VC-1 AR 15 Flash Hider

VLTOR VC-1 Flash Hider for AR 15 Style Semi Automatic Assault Rifles

VLTOR VC-1 Flash Hider for AR 15 and Modern Sporting Rifles

VLTOR VC-1 Flash Hider – Highly-efficient internal helical design uses ten precisely contoured longitudinal ports combined with a unique, cloverleaf-shaped exit port to trap un-burned powder particles long enough for full burn and dissipation of hot combustion gasses. Muzzle flash cancels itself out to minimize shooter exposure during daytime and low-light situations. Also serves as a compensator by directing venting gasses to help reduce muzzle jump and improve shooter control for better shot placement. Precision machined from 4140 steel to stand up to rough tactical operations. 2-1/8″ overall length brings a 14 1/2″ barrel up to legal length for civilian use when flash suppressor is permanently pinned or welded in place. Accepts most sound suppressors and Blank Firing Attachments designed to fit a M16/M4 flash hider. VC-1 fits .223/5.56mm AR-15/M16/M4 rifles; VC-301 fits .308/7.62mm AR-style rifles.

 


Colt Sporter Tactical Lower Receiver

Magpul ACS AR 15 Stock

Magpul ACS AR 15 Stock Picture

Magpul ACS Stock

The lower upgrade was an easy choice. I never cared for A2 buttstock’s and in the case of this weapon it also had an optional cheek riser to aid in sighting with my carry handle optics. The buttstock with the cheek riser weigh quite a bit and weight reduction is one of the primary reasons for this project. I will include a weight comparison at the end of this project.

My choice for buttstock is the collapsible Magpul ACS Mil Spec in black. Below is the manufacturers information.

 

The Adaptable Carbine/Storage stock (ACS) features an integrated storage compartment located at its tail for spare parts and other gear, dual water-tight battery storage tubes on either side, and a replaceable 0.30″ rubber butt pad that provides an anti-slip surface and added protection from impact damage. Also features the unique cam-lock design pioneered by Magpul’s CTR stock, enhancing stability and accuracy potential by anchoring the stock tightly to the buffer tube with minimal wobble. A sloping cheek weld surface and shielded release latch further contribute to the stock’s ergonomic, user-friendly design. Compatible with the ASAP and other receiver mounted sling adapters, with provisions for adding push button QD sling mount sockets (not included) for right or left handed sling positioning. Buffer, buffer tube, and recoil spring not included.

Technical Information:

  • Base Stock Weight: 0.86 lb
  • Base Stock Length: 7.93 in
  • Length of Pull (LOP) Adjustment Range: 3.3 in
  • LOP Fully Collapsed: 11.45 in
  • LOP Fully Extended: 14.75 in

I will include a weight comparison at the end of this project.

American Trigger Corp AR Gold Trigger

I like the folks from American Trigger/PACT.  The American Trigger Corp AR Gold Trigger as well as their SR Gold are my favorite modular drop in triggers for the AR-15 and 308AR platforms. If the cost is out of reach the CMC Triggers are my next runner up in the drop in modular trigger category. The cost of the CMC Triggers are beginning to close in on the AR Gold

American Trigger Corp AR Gold Trigger for AR 15

American Trigger Corp AR Gold Trigger

AR 15 Carbine Mil Spec Stock Completion Kit

Carbine Mil Spec Stock Completion Kit for AR 15 Semi Auto rifles

Carbine Mil Spec Stock Completion Kit

This kit was the easiest way to get the correct receiver extension tube, carbine buffer, buffer spring to complete the build. Brownells put all the parts in one bag. Now after the fact they have a kit that includes the Magpul ACS. Story of my life.

 

Young Manufacturing National Match Bolt Carrier

Young Manufacturing Chrome Match Bolt Carrier Group for AR 15 Rifles

Young Manufacturing Chrome AR 15 Match Bolt Carrier Group

I bought the Young Manufacturing National Match Stripped Bolt Carrier direct from the factory. Im quickly becoming a fan of the quality of their products. The bolt carrier will be finished.  The other items needed to complete the carrier are:

The parts can be purchased as an AR-15 Bolt Carrier Completion Kit but that will supply a matte key rather than chrome.


Metal Finishing

US Anodizing

Anodized Preban Colt Sporter

Anodized Preban Colt Sporter

Today most AR-15 receivers are some variation of black. Unfortunately my Colt Sporter is a pre ban gray/blue in color. Now I’m not particularly fussy when it comes to the appearance of my guns but mating the Colt Sporter lower with a black upper looks plain awful and something needs to be done. Many folks suggested various coatings such as Duracoat and Cerakote or getting my Colt Sporter lower re-anodized black. I wasn’t fond of any of those solutions. Finally Draco41 over at 308forum pointed me to Victor at US Anodizing Victor was patient responding to all my questions in a timely fashion. Victor stated that he knew the exact color I was after and could get it pretty close on my new stripped upper.

 


Back Up Iron Sights BUIS

Getting the Troy Battle Sights was always the plan yet I almost wavered at the last moment and went with the GG&G sights. The DOA aperture brought me back to the Troy side. Truth be told both brands of sites are premium quality.

Troy BattleSight Front HK Folding

Troy AR 15 BattleSight Front HK Folding

Troy BattleSight Front HK Folding AR 15 Front Sight

Troy BattleSight Front HK Folding-Durability and dead-on accuracy have made Troy Industries Folding BattleSights the hands-down choice of Special Ops and tactical users worldwide. Easy to install and to deploy, with no levers or springs to fumble with, these sights position apertures at exact factory height. A stainless-steel cross-locking system ensures sights remain upright and zeroed under extreme combat conditions. A push of a button folds the sights securely out of the way until you need them again (they fold to a profile of just 0.460). Troy BattleSights feature a zero-canting attachment system for use on all military and aftermarket receivers. No tools required for adjustment. Each click adjusts .50 MOA.

 

Troy BattleSight Rear Di-Optic Aperture (DOA) Folding

Troy AR 15 BattleSight Rear Di-Optic Aperture DOA Folding

Troy BattleSight Rear Di-Optic Aperture DOA Folding AR 15 Rear Sight

Troy BattleSight Rear Di-Optic Aperture (DOA) Folding – Advanced design, superior sighting and battle-ready toughness define Troy Industries’ Di-Optic Aperture (DOA) Folding Rear BattleSight.

These sights provide lightning fast target acquisition and are manufactured to exceed military specs. The optically engineered apertures center your eyes instantly and effortlessly providing a clearer target picture than with round apertures.

The sights feature two settings, one for up to 300 meters and a second for up to 500 meters. This versatility makes the DOA ideal for military, law enforcement and home defense applications. These advanced sights have been extensively field-tested and, like all Troy Industries products, are Battle Ready. Note: Sight is designed to work on same plane rail systems only. Will not work with a railed gasblock that is higher or lower than the receiver.

 


Optics

EOTech 557 AR223 Holographic Weapon Sight (HWS) Night Vision Compatible (M557)

The EOTech 557 AR223 Holographic Weapon Sight (HWS) Night Vision Compatible (M557) was a gift from my lady and perfect for this application.

EOTech 557 AR223 AR 15 Holographic Sight

EOTech 557 AR223 AR 15 Holographic Sight


UTG Defender Weapon and Handheld Tactical Xenon Flashlight LT-ZL168

UTG DEFENDER TACTICAL LIGHT

UTG DEFENDER TACTICAL LIGHT

I wanted to see how well an inexpensive tactical light would perform as a taclight wasnt in the budget for this project. I settled on the $35 UTG LT-ZL168. It was priced similarly everywhere, I got mine from Amazon.

I have not mounted it on the weapon yet but I did some informal trials around the house and outside. The light is very bright, in fact much brighter than any other battery operated light I own. At a later time I plan on purchasing a higher output model for comparison sake.

 

Here is the factory specifications.

  • Model: LT-ZL168
  • Bulb Type: 26MM Xenon IRB (Integrated Reflector and Bulb)
  • Voltage: 6V Max. Output: 126 Lumens
  • Battery Operating Time: 70 mins
  • Weight with Batteries: 5.6 oz
  • Main Body Diameter: 1.00″
  • Length: 5.22″
  • Battery/Qty: CR123A x 2
  • Pressure Switch: Included
  • Mount/Ring: Slide-on Tactical Style Ring
  • Focus: Preset

Features:

  • Patterned Surface for Easy Gripping
  • Integrated Reflector & Bulb and Preset Focus
  • Handheld and Weapon-Mount
  • Law Enforcement Rated Rolling Stop Shoulder
  • Tail Push-button Momentary Switch and End-cap Twist-on Switch
  • Complete with Remote Pressure Switch and Tactical Slide-on Ring Mount
  • Two 3-volt Lithium Batteries Included

LaserMax Mantarail Momentary Switch Control System

LaserMax Mantarail Handguard Mounted Light Switch for Tactical Type Assault Rifles

LaserMax Mantarail

I didnt want the typical glued on pressure switch for the tactical light and possibly future laser. After a bit of searching I found this LASERMAX MANTARAIL. The Mantarail is pretty clever, it consists of a hollow rubber pocket that can house pressure switches. The back of the MantaRail is molded to attach to a picatinny base. Inside the pocket are two rods the allow the pressure switches to be activated by squeezing the Mantarail just about anywhere along its length. The MantaRail also includes clips for routing the wires along your picatinny in a clean manner.

AR 15 Hanguard Mounted Light Switch the LaserMax Mantarail

LaserMax Mantarail

 


AR 15 Tools

Every job has it tools, hopefully you already have the following tools on hand. If not you should.